Voltage regulator



July 11, 1950 1.. E. STILPHEN 2,514,908

VOLTAGE REGULATOR Filed Sept. 30, 1948 3 Sheets-Sheet 1 gay/L54 LQQIEM C m, Y W

ATTOR N EYQ July 11, 1950 L. E. STILPHEN 2,514,908

VOLTAGE REGULATOR Filed Sept. 30, 1948 3 Sheets-Sheet 2 L S E a awuzm fom ATTORNEYS J 11, 1950 Y L. E. STILPHEN 2,514,908

v VOLTAGE REGULATOR Filed Sept. 30, 1948 3 Sheets-Shee't 5 INVENTOR wazz. g

ATTORNEYS Patented July 11, 1950 UNITED STATES PATENT OFFICE VOLTAGE REGULATOR Lee E. Stilphen, Plymouth, N. H. Application September 30, 1948, Serial No. 51,957

6 Claims.

This invention relates to voltage regulators to be used in alternating current circuits. More particularly, it relates to voltage regulators which effect the voltage regulation by varying the reluctance of a magnetic circuit which is associated with the alternating current circuit which is to be regulated.

An object of this invention is to provide a voltage regulator which is simple and rugged in construction but nevertheless is capable of effecting exact voltage control of the regulated circuit. In the voltage regulator provided all constituent parts of the regulator can be formed by simple stamping or machining operations and assembled with minimal difliculty. The invention provides a regulator in which the movable element is designed in a regular balanced form and devoid of components of motion in operation which act to set up vibration or strain in the voltage regulator which impairs its efficiency or its operation.

A further important feature of the present invention is the provision of a short circuited coil acting with the core-piece which is easily assembled on the core-piece and automatically positioned to substantially increase the regulating efficiency of the voltage regulator.

Additionally, the present invention provided a core-piece and the magnetic elements of the magnetic circuit in a relationship which substantially increases the regulatory effect of the voltage regulator.

Another object is to provide a novel means of selecting certain magnetic circuits in response to signals from a voltage responsive device in order to vary the reluctance of the associated magnetic circuit and thereby effect the voltage regulation of the circuit to be regulated, and to provide in conjunction therewith means for disconnecting from the magnetic circuit the nonselected magnetic circuit.

Further objects and advantages of the invention will be apparent from the following detailed description made with reference to the accompanying drawings. It is to be understood that the embodiment of the invention illustrated in the accompanying drawings and described in detail hereafter is not intended to limit the invention as there set forth. Various changes and modifications such as would occur to one skilled in the art to which this invention relates are contemplated within the scope of the invention.

In the accompanying drawings:

Figure 1 shows an elevational view of a voltage regulator embodying a preferred form of the invention;

Figure 2 is a side view with a portion of the regulator casing cut-away to illustrate the shape of the magnetic cores and the relationship of the cores to the coils and core-piece;

Figure 3 is an end view of a modified form of the core-piece;

Figure 4 is a side view of the modified form of the core-piece, and

Figure 5 is a diagrammatic view of the voltage regulator in a preferred form showing the associated electrical circuits.

Figure 6 is a circuit diagram illustrating the electrical circuits employed to connect the instant voltage regulator into a power line in which it is desired to regulate the voltage.

In the embodiment of the invention illustrated in Figures 1 and 2, the magnetic cores l0, H and [2 are rigidly affixed to the common member 13. All of these members may be made up of a number of thin laminations in the form commonly adapted in the construction of magnetic cores. The core-pieces l0 and I2 are formed with arcuate concave sections l4 and I5 and the corepiece I l with a concave section of the same radius at I6. The radii of the concave sections is determined with reference to the radius of the corepiece H, the radius of thearc defined by the concave sections being large enough to receive the core-piece I! in concentric relationship and define an air-gap between said core-piece and the several cores I 0, H and I2. I

Coils l8, l9 and 20 are mounted respectively, on the lower portion of the cores I0, H and I2. These coils may be wound on a lathe and slipped down over the respective cores into place on the cores thus easily facilitating changing the characteristic of the voltage regulator as may be suitable in connection with the particular circuit to be regulated.

A frame 2| of non-magnetic material is constructed around the upper portion of the regulator. The frame consists of the panels 2| which are appropriately joined at their abutting edges. The frame 2| serves to secure the cores I0, I I and i2 in spaced relationship and carries the bearings 22 and 23. The rotatable shaft 24 is journaled in said bearings and adapted for rotation therein.

The core-piece I7 is mounted on the central portion of the shaft 24 and secured by suitable means against rotation relative thereto. In the preferable form of the invention the core-piece l1 consists of a plurality of relatively thin laminations of silicon steel.

The core-piece ll may be a cylindrical sector in form, the flat surface formed by removal of aciaeoe the complementary sector of the form being nor anally positioned above the core=piece it as illustrated in Figure 2 and thus iorming an air gap 32 between the core-piece W and the core ll.

It has been discovered that the voltage regulator will perform with equally satisfactory results if the core-piece it is designed in the shape of a cylinder as illustrated in Figures 3 and 4 and provided with slots 25 in the cylindrical surface parallel to the axis of the cylinder into which a sell-short circuited coil 26 is wound. This modification of the core-piece is illustrated in Figures 3 and d. The self-short circuited coil acts to prevent the flow of flux into the core from undesired sources during the operation of the voltage regulator. The same effect is produced when the self-short circuited coil is used in connection with a core-piece of cylindrical sector form as illustrated in Figure 2.

A control wheel 2?? is rigidly afiixed on the end portion of the shaft 26 extending through the bearing 22. A pin 28 is carried by the control wheel and positioned in relation to switching means in the magnetic circuit, as explained in detail hereafter, to contact and operate said switching means. The drive gear 29 is mounted on the other end of shaft 241 and rigidly amxed thereto, thereby rotating the said shaft and the amxed elements as a unit upon movement of the gear wheel.

A plate till mounted on the frame 2i carries a motor ill, the armature shaft of which carries the pinion 82 adapted to engage the gear wheel 29. The motor f-ll is reversible in direction by virtue of having one coil adapted to rotate the armature shaft in a clockwise direction and a second coil operating in turn to rotate the armature shaft in a counterclockwise direction. The direction of rotation of the motor and the conseuent direction of movement of the shaft assembly is controlled by a voltage responsive means as will hereinafter be explained in detail.

The voltage regulator assembly as described is associated in electrical connection with a voltage responsive means which functions to detect voltage variations in the circuit to be controlled and initiate signals which result in selecting a magnetic circuit by means of the rotation of the core-piece into said selected circuit and simultaneously therewith cutting out of the magnetic circuit a non-selected coil.

Referring to figure 5, this regulation is achieved by providing a contact making voltmeter 33 connected in the circuit to be regulated and connecting the voltmeter to the relays 3d and 3t, relay 36 being actuated when the voltmeter signals a drop in the line voltage and relay 35 when a rise has been signalled. The relays 34S and 35 are connected in the feed line to the motor ii.

The coil it is connected in series with the circuit to be regulated. The remaining two coils l8 and 20 are connected in parallel to the series coil, the connection across the line being made through the switch 38 in the case of coil it and through the switch ill in the case of coil 26.

In normal position when the voltage in the circuit to be regulated corresponds to the desired voltage switches 36 and 3'5 will be closed and.

coils l8 and 20 will be connected in parallel across the line. The windings of the coils I8 and 2d are such that both have a polarity which generate flux in the same direction around the cores it and I2, thus the coils will induce flux in opposite directions in the series coil it when switches 38 and 3? are both closed and coils l8 and 26 are connected ar The switches and M are the cne=way switch and positioned in relation to the pin so that as the pin is carried in t .e direction of one of. the switches it willcontact the switch button, depress the switch button, and operate the switching means, and pass over the switch but ton leaving the switch in the newly set position. if the motor Ell continues to rotate the control wheel 21] carrying the pin 23 in response to a signal from the voltage responsive means 233, the pin will be rotated into contact with the limit swimh S8 or 39. The feed circuit to the directional coils of the motor Si is completed through the switches till and 89, whereby the feed circuit to the particular directional coil circuit is interrupted when the limiting switch in said coil circuit has been operated by contact with the pin 28. It will be seen that the other coil circuit governing movement of the shaft assembly carrying the pin 29 in the opposite direction will remain closed and ready to respond to a signal for movement in the direction controlled by that particular coll.

A voltage regulator constructed and connected in the circuit to be regulated as above described and in neutral position as illustrated in Figure 5 will respond to a drop in voltage by the voltmeter 33 operating to close the contacts at it thereby energizing the relay 3d. The relay 3G thereupon closes the contact M and completes the circuit to the motor field coil which causes rotation of the shaft 26 carrying the control wheels El with the pin 28 and the iron core-piece ill in a counterclockwise direction. The rotation of the iron core-piece in this direction will close the magnetic circuit between the parallel coil 2d and the series coil it, and as the pin 28 is rotated into contact with the switch 3%, and the switch operated thereby, the parallel coil it will be cut out of the magnetic circuit. The polarity of the parallel coil 2b is such that flux will thereupon be forced to pass in the series coil it in a direction which opposes the current flow in the series coil and thereupon increases the reluctance of the magnetic circuit which acts to correct the voltage drop in the regulated circuit. At the same time the rotation of the iron core-piece ill will move the air gap 32, the air gap and the self-short circuited winding or the winding alone, depending on the modification of the iron corepiece selected, into position between the cutout parallel coil l8 and the series coil is thus preventing flux from undesired sources interfering with the bucking or boosting eifect of the parallel coil connected in the magnetic circuit. Further rotation of the pin 25 will cause the limiting switch 38 to be operated and the feed circuit to the counterclockwise coil of the motor will be opened. The feed circuit to the clockwise, or voltage bucking direction, will remain closed except for the relay 85. en the regulated circuit voltage becomes higher than desired the voltmeter will close the contact 68 and the relay 35 will be energized thus completing the feed circuit to the clockwise motor coil and the cycle of operation described above will be repeated in the reverse direction. Voltage regulation may thus be attained with small fluctuations and without sparking during operation of the voltage regulator since the parallel coils, being of a polarity which generate flux in the same direction in the parallel coll cores and in opposite direction in the series coil, will induce approximately the same voltage in the disconnected parallel coil so that when the parallel coils are connected or disconnected very little voltage differential will exist between the leads of the two parallel coils.

Having described the invention, that which is claimed as new and is desired to be secured by Letters Patent is:

1. A transformer device adapted for use in an alternating current voltage regulation circuit comprising three aligned magnetic cores, coils positioned around one portion of said cores, the centrally positioned one of said coils being adapted for series connection into a circuit to be regulated, the remaining two coils being normally in parallel connection with said series coil and of polarity to induce flux in opposite directions through said series coil, another portion of said cores being provided respectively with concentric arcuate declivities to form a central opening, a core-piece rotatably supported in said opening and adapted for connection to means which rotate said core-piece in one direction in response to a voltage rise in the circuit to be regulated and in the other direction in response to a voltage drop in said circuit, and means controlled by the movement of said core-piece in one direction for disconnecting one of said coils normally in parallel with said series coil, the said core-piece movement in the said one direction positioning the core-piece to complete a magnetic circuit between the other said parallel coil and said series coil, whereby the movement of said core-piece completes a magnetic circuit between one of said coils normally in parallel with said series coil and the said series coil, and the other said coil normally connected irrparallel with said series coil is disconnected.

2. A transformer device adapted for use in an alternating current voltage regulation circuit comprising three aligned magnetic cores, coils positioned on one portion of said cores, the centrally positioned one of said coils being adapted for series connection into a circuit to be regulated, the remaining two coils being normally in parallel connection with said series coil and of polarity to produce flux in opposite direction through said series coil, another portion of said cores being provided respectively with concentric arcuate declivities to form a central opening, a core-piece in form of a cylindrical sector rotatably supported in said opening and adapted for connection to means which rotate said core-piece in one direction in response to a voltage rise in the circuit to be regulated and in the other direction in response to a voltage drop in said circuit, the flat portion on said core-piece being positioned normally immediately above the core supporting said series coil, and means controlled by the movement of said core-piece in one direction for disconnecting one of said coils normally in parallel with said series coil, the core-piece movement in the said one direction moving the said fiat portion of said core-piece toward said which comprises a short-circuited winding supported on said core-piece immediately adjacent the flat portion of said sector, and with the plane of the said winding parallel to the plane of said fiat portion of said core-piece.

4. A transformer device as claimed in claim 3 in which said means controlled by the movement of said core-piece for disconnecting one of said coils normally in parallel with said series coil comprises switching means in the parallel connections of said two remaining coils to said series coil, and a pin carried on said rotatable core-piece positioned to contact and operate said switching means when said core-piece is rotated.

5. A transformer device adapted for use in an alternating current voltage regulation circuit comprising three aligned magnetic cores, coils positioned on one portion of said cores, the centrally positioned one of said coils being adapted for series connection into a circuit to be regulated, the remaining two coils being normally in parallel connection with said series coil and of polarity to induce flux in opposite direction through said series coil, another portion of said core being provided respectively with concentric arcuate declivities to form a central opening, a core-piece cylindrically in form rotatably supported in said opening and adapted for connection to means which rotate said core-piece in one direction in response to a voltage rise in the circuit to be regulated and in the other direction in response to a voltage drop in said circuit, a short-circuited winding supported on said corepiece, said winding being normally positioned immediately above the core supporting said series coil, and means controlled by the movement of said core-piece in one direction for disconnecting one of the said coils normally in parallel with said series coil, the core-piece movement in the said one direction moving the said short-circuited winding on said core-piece toward said disconnected parallel coil, the cylindrical portion of said core-piece then completing a magnetic circuit between the other of said parallel coils and said series coil, whereby the movement of said corepiece completes a magnetic circuit between one of said coils normally in parallel with said series coil and the said series coil, and the other said coil normally connected in parallel with said series coil is disconnected.

6. A transformer device as claimed in claim 5 in which said means controlled by the movement of said core-piece for disconnecting one of said coils normally in parallel with said series coil comprises switching means in the parallel connections of said two remaining coils to said series coil, and a pin carried on said rotatable coredisconnected parallel coil, the cylindrical portion as of said core-piece then completing a magnetic circuit between the other of said parallel coils and said series coil, whereby the movement of said core-piece completes a magnetic circuit between one of said coils normally in parallel with said series coil and the said series coil, and the other said coil normally connected in parallel with said series coil is disconnected.

3. A transformer device as claimed in claim 2 v piece positioned to contact and operate said switching means when said core-piece is rotated.

LEE E. STILPHEN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,716,553 Higbee June 11, 1929 1,897,415 Barbour Feb. 14, 1933 2,306,000 Stilphen Dec. 22 1942 FOREIGN PATENTS Number Country Date 709,923 France Aug. 14, 1931 

